It is the first time since 1981 that four American women have made the semi-finals in New York, and the first time anywhere since Wimbledon 1985.
Madison Keys outplayed Kaia Kanepi to complete an all-American line-up in the US Open women’s semi-finals. The 15th seed won 6-3 6-3 to join Coco Vandeweghe, Venus Williams and Sloane Stephens in the last four.
Vandeweghe, seeded 20th, earlier beat Czech top seed Karolina Pliskova 7-6 (7-4) 6-3.
Williams, 37, is the only one of the four Americans to have reached a Grand Slam final, the first of which came at Flushing Meadows 20 years ago.
Stephens, 24, made history herself Tuesday by becoming the first American woman besides the Williams sisters to advance to the semifinals in the U.S. Open.
She has since racked up seven major titles, including victories at the US Open in 2000 and 2001, and she will take on the unseeded Stephens in Thursday’s semi-finals.
Keys and Vandeweghe will follow them onto Arthur Ashe Stadium as home players sweep the final four.
“This means the world to me,” said Keys.
“I’m just so happy to be here. We’re going to have four American women playing tomorrow, and that’s pretty awesome.”
The 22-year-old brushed aside Kanepi in just 69 minutes without dropping serve, breaking once in the first set and twice in the second.
Kanepi’s presence in the quarter-finals was remarkable in itself, having come through qualifying ranked 418th after two years of injury and illness.
However, Keys fired down eight aces among 23 winners as she dominated in the opening night-session contest.
Having seen Williams and Stephens progress on Tuesday, followed by Vandeweghe earlier on Wednesday, Keys admitted she had been feeling the pressure.
“I was real nervous today,” she said. “The car ride over I was definitely feeling it, but once I got out here I felt really good.”
Vandeweghe, 25, paid tribute to Venus and Serena Williams among recent American players to have inspired the current generation.
“Venus last night said it very well, that the younger ones were looking at Lindsay [Davenport], Jennifer [Capriati], and Serena and Venus,” said Vandeweghe.
We wanted to be those same players in a later generation. Now that we’re older, we can put that into words, but we all wanted to be there.”
Evert, an 18-time Grand Slam champion, told ESPN: “I’m so happy for the American players, they’ve gotten such criticism over the last 10 years.
“Finally the influence of Serena and Venus has full effect on all the young ladies, who always mention them when they talk about role models.”